Diamonds are gemstones made of pure carbon. On Earth, they can form only under the high pressure and temperature conditions deep within the Earth’s mantle. The diamonds that we find on (or near) the surface have been transported from great depths at enormous speeds by explosive magmas. Since their first discovery, geologists have been fascinated by how, why, and when diamonds form. However, answering these questions is difficult because a diamond’s pure carbon composition makes dating diamond itself almost impossible.

Dr Janne Koornneef and colleagues at the Vrije Universteit in Amsterdam, the Netherlands, have recently developed techniques that make it possible to date diamonds by studying mineral ‘inclusions’ trapped within the diamond structure. These techniques allow researchers — for the first time — to determine precisely when and by what process diamonds form. The results have led to great surprises, including that some diamonds can form at a much younger geological age than previously expected.

In this webinar, Dr Koorneef will explain what we currently know about diamond formation and the mysteries that geologists still hope to solve about these iconic and beautiful gemstones.

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 654208.